Using a gastroscopy to view an upper gastrointestinal tract is common. The endoscope helps surgeons evaluate various symptoms that include persistent abdominal pain, nausea vomiting, and bleeding. Moreover, the gastroscopy is a very excellent tool for treating the cause of bleeding in the upper gastrointestinal tract. However, after treating the cause of bleeding, re-bleeding could possibly occur in few days later. Depending on the amount of blood loss, re-bleeding could cause shock and even lead to death.
To our knowledge, there is no medical device that can automatically and consistently detect re-bleeding in the upper gastrointestinal tract. The second gastroscopy may be used for checking the re-bleeding condition. But, the second gastroscopy is applied only when re-bleeding is confirmed by fecal occult blood, low blood pressure, or hematemesis. However, these indirect sings of re-bleeding mean that the re-bleeding has lasted for a while or the blood loss has reached certain amount.
A capsule endoscopy may be used for detecting the re-bleeding in the upper gastrointestinal tract. Although the capsule endoscopy can provide real-time images of the upper gastrointestinal tract, the capsule quickly passes through esophagus, stomach, and duodenum to the lower gastrointestinal tract. Because the monitoring period is short and the device is costly, it is not applied in the re-bleeding detection. The capsule endoscopy has drawbacks, because it cannot stay and monitor re-bleeding in the upper gastrointestinal tract for several days due to power shortage. A conventional optical detection capsule is to detect spectrum absorption of body liquid permeating into a detecting optical path, which differs from an analysis on reflection from body liquid. However, such ideas have not been scientifically approved because gastric contents and food intake could significantly influence the detection and analysis. Some capsules do not exhibit any detection function for bleeding. For optical detection, plaque measurement within vascular wall is used, in which plaques of non-blood subjects such as lipid, cholesterol, and leukocyte body aggregation are detected for analysis on invisible absorption spectrum of specific subjects.